Conventionally, there exist rotation devices for rotating a rotary member using an actuator which operates by being supplied with fluid, such as air or liquid. The actuator applied to this kind of rotation device has a tube shape as a whole, and is often a type in which a dimension in a diameter direction perpendicular to the full length direction thereof is inflated by the supply of fluid (a type called a McKibben type or hydraulic type actuator).
FIGS. 10(a) and 10(b) show a conventional common rotation device 1. In the conventional rotation device 1, a plate-shaped rotary member 3 is rotatably coupled to one end part 2a of an elongated-plate-shaped placement member 2 (a rotation center is a rotation shaft 9), and a tube-shaped, hydraulic type actuator 4 is arranged on an upper face 2b of the placement member 2. The actuator 4 is attached with a wire material 5 at a tip 4a thereof, and an end part 5a of the wire material 5 is coupled to an upper face 3a of the rotary member 3 via an anchor 6. In addition, the actuator 4 connects with a hose 7 for fluid (for example, air) supply at a rear end 4b thereof, and the hose 7 is fixed to the upper face 2b of the placement member 2 by a fixing member 8, thereby the actuator 4 is fixedly attached to the placement member 2.
From a state of FIG. 10(a), when the fluid is supplied to the actuator 4 through the hose 7, the actuator 4 is inflated as shown in FIG. 10(b). Here, the full length of the actuator 4 parallel to the X-direction in this figure (the longitudinal direction of the placement member 2) shrinks, and the radial dimension of the actuator 4 parallel to the Y-direction in this figure (the thickness direction of the placement member 2) expands. Therefore, the actuator 4 pulls the rotary member 3 via the wire material 5. The actuator 4 pulling the rotary member 3 rotates the rotary member 3 by an angle α from the state shown in FIG. 10(a) centering on the rotation shaft 9. FIG. 10(b) shows a state in which the actuator 4 is inflated to the maximum extent, and in this state, it is assumed that the wire material 5 is in parallel to the X-direction.
Components equivalent to the rotation device 1 as shown in FIGS. 10(a) and 10(b) described above are also disclosed in the following Patent documents 1 to 3.